Merge pull request #3887 from branh/patch-2

Clarify master and single directives.

Author: jborsecnik

docs/parallel/openmp/reference/openmp-clauses.md

@@ -32,12 +32,12 @@ For data-sharing attributes:
 |[shared](#shared-openmp)|Specifies that one or more variables should be shared among all threads.|
 |[default](#default-openmp)|Specifies the behavior of unscoped variables in a parallel region.|
 |[reduction](#reduction)|Specifies that one or more variables that are private to each thread are the subject of a reduction operation at the end of the parallel region.|
-|[copyin](#copyin)|Allows threads to access the master thread's value, for a [threadprivate](openmp-directives.md#threadprivate) variable.|
+|[copyin](#copyin)|Allows threads to access the main thread's value, for a [threadprivate](openmp-directives.md#threadprivate) variable.|
 |[copyprivate](#copyprivate)|Specifies that one or more variables should be shared among all threads.|
 
 ## <a name="copyin"></a> copyin
 
-Allows threads to access the master thread's value, for a [threadprivate](openmp-directives.md#threadprivate) variable.
+Allows threads to access the main thread's value, for a [threadprivate](openmp-directives.md#threadprivate) variable.
 
 ```cpp
 copyin(var)
@@ -46,7 +46,7 @@ copyin(var)
 ### Parameters
 
 *var*<br/>
-The `threadprivate` variable that will be initialized with the variable's value in the master thread, as it exists before the parallel construct.
+The `threadprivate` variable that will be initialized with the variable's value in the main thread, as it exists before the parallel construct.
 
 ### Remarks
 
@@ -513,7 +513,7 @@ int main() {
    printf_s("These are the variables after exit from "
             "the parallel region.\n");
    printf_s("nThreadPrivate = %d (The last value in the "
-            "master thread)\n", nThreadPrivate);
+            "main thread)\n", nThreadPrivate);
    printf_s("      nPrivate = %d (The value prior to "
             "entering parallel region)\n", nPrivate);
    printf_s(" nFirstPrivate = %d (The value prior to "
@@ -591,7 +591,7 @@ nFirstPrivate = 3
        nShared = 3
 
 These are the variables after exit from the parallel region.
-nThreadPrivate = 0 (The last value in the master thread)
+nThreadPrivate = 0 (The last value in the main thread)
       nPrivate = 4 (The value prior to entering parallel region)
 nFirstPrivate = 4 (The value prior to entering parallel region)
   nLastPrivate = 3 (The value from the last iteration of the loop)

docs/parallel/openmp/reference/openmp-directives.md

@@ -19,13 +19,13 @@ For parallel work-sharing:
 |[parallel](#parallel)|Defines a parallel region, which is code that will be executed by multiple threads in parallel.|
 |[for](#for-openmp)|Causes the work done in a `for` loop inside a parallel region to be divided among threads.|
 |[sections](#sections-openmp)|Identifies code sections to be divided among all threads.|
-|[single](#single)|Lets you specify that a section of code should be executed on a single thread, not necessarily the master thread.|
+|[single](#single)|Lets you specify that a section of code should be executed on a single thread, not necessarily the main thread.|
 
-For master and synchronization:
+For main thread and synchronization:
 
 |Directive|Description|
 |---------|-----------|
-|[master](#master)|Specifies that only the master thread should execute a section of the program.|
+|[master](#master)|Specifies that only the main thread should execute a section of the program.|
 |[critical](#critical)|Specifies that code is only executed on one thread at a time.|
 |[barrier](#barrier)|Synchronizes all threads in a team; all threads pause at the barrier, until all threads execute the barrier.|
 |[atomic](#atomic)|Specifies that a memory location that will be updated atomically.|
@@ -356,7 +356,7 @@ The sum of 1 through 10 is 55
 
 ## <a name="master"></a> master
 
-Specifies that only the master thread should execute a section of the program.
+Specifies that only the main thread should execute a section of the program.
 
 ```cpp
 #pragma omp master
@@ -369,14 +369,13 @@ Specifies that only the master thread should execute a section of the program.
 
 The `master` directive supports no clauses.
 
-The [single](#single) directive lets you specify that a section of code should be executed on a single thread, not necessarily the master thread.
-
 For more information, see [2.6.1 master construct](../2-directives.md#261-master-construct).
 
+To specify that a section of code should be executed on a single thread, not necessarily the main thread, use the [single](#single) directive instead.
+
 ### Example
 
 ```cpp
-// omp_master.cpp
 // compile with: /openmp
 #include <omp.h>
 #include <stdio.h>
@@ -606,7 +605,7 @@ Hello from thread 0
 
 ## <a name="single"></a> single
 
-Lets you specify that a section of code should be executed on a single thread, not necessarily the master thread.
+Lets you specify that a section of code should be executed on a single thread, not necessarily the main thread.
 
 ```cpp
 #pragma omp single [clauses]
@@ -629,10 +628,10 @@ The `single` directive supports the following clauses:
 - [copyprivate](openmp-clauses.md#copyprivate)
 - [nowait](openmp-clauses.md#nowait)
 
-The [master](#master) directive lets you specify that a section of code should be executed only on the master thread.
-
 For more information, see [2.4.3 single construct](../2-directives.md#243-single-construct).
 
+To specify that a section of code should only be executed on the main thread, use the [master](#master) directive instead.
+
 ### Example
 
 ```cpp